Dissection of the molecular interaction network between the bacterial effector protein AvrBs1, the corresponding NLR protein Bs1, and the receptor kinase FEI1

• Applicant: Professor Dr. Thomas Lahaye
• Subject Area: Organismic Interactions, Chemical Ecology and Microbiomes of Plant Systems
• Term: since 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 550936204

Bacterial pathogens inject effector proteins into plant cells and manipulate plant immunity to favor infection. The identification of effector target proteins and the elucidation of the mechanisms by which effectors manipulate the function of target proteins opens the possibility of generating crop plants with improved disease resistance. We study the interaction between pepper plants carrying the Bs1 resistance gene and AvrBs1, an effector protein of the bacterial pathogen Xanthomonas that induces a Bs1-dependent immune response. In preliminary work, we have identified FEI1, a receptor-like kinase, as an AvrBs1 target protein using a genetic screen. In this proposal, we aim to clarify the molecular relationships between AvrBs1, the corresponding host target FEI1 and the resistance protein Bs1. The FEI1 protein is predicted to be a membrane-bound co-receptor that senses changes in cell wall integrity. Since changes in cell wall integrity occur in the context of both plant developmental programs and bacterial infection, we aim to elucidate how FEI1 discriminates between these different signals and subsequently initiates appropriate cellular programs. Ultimately, the new mechanistic insights into the molecular basis of plant-microbial pest interactions open up new possibilities for creating pathogen-resistant crops through targeted modification of the host genome. Our findings are therefore not only important for basic plant research but also for applied plant breeding.

• DFG Programme: Research Grants
• International Connection: South Korea
• Cooperation Partner: Professor Kee Hoon Sohn, Ph.D.